Russia has put its security officials on combat alert after five people were found dead in their cars less than a month before the Sochi Olympics in an apparent act of terrorism.

Police in Russia are searching for three suspected Islamist terrorists who allegedly shot five people and booby trapped two of their vehicles in the Stavropol region, a mere 186 miles from Sochi.

Russian sources named three suspects, Anzor Margushev, 32, his brother Artur, 23, and Vadim Shogenov, 25, from the neighboring Kabardino-Balkaria region in the crime.

Two of the alleged militants are wanted for a prior murder on Oct. 29. At that time, Russian investigators told a Russian news website, the Caucasian Knot, that they suspected both men of belonging to the terrorist Islamist group the KBK Vilayat.

Authorities found the victims, two of whom were taxicab drivers, near the villages of Tambukan, Zolskaya and Mariinskaya. When detectives approached one vehicle, an explosive device went off but on one was injured, according to reports.

The taxi slaughter is one of several acts of violence before the Winter Olympics which begin Feb. 7.

Russian media reported that police arrested a woman wearing a suicide bomb belt while riding on a bus in Stavropol, although Russian officials have not confirmed the incident.

And two suicide bombers killed 34 people in Volgograd — about 600 miles from Sochi — on Dec. 29 and 30.

Russian governmental officials have ramped up security during the Winter Games in response.

About 37,000 police and interior ministry officials will provide security in Sochi. But the city is near the North Caucus region and the mainly Muslim region of Chechnya where separatist rebels have fought Russian troops for more than a decade.

Russian President Vladimir Putin said he would destroy all terrorists in Russia after the Volgograd attacks. Chechen rebel leader Doku Umarov has urged his forces to target the games.